If you look at the ReadTheDocs documentation at https://docs.readthedocs.io/en/stable/index.html, the bottom of the nav pane provides options for selecting another version as well as viewing the PDF, HTML, and epub versions of the doc. However, in the Writing Fundamentals Guide, this section of the nav pane isn't there. Instead, there's a version drop-down in the lower right corner, but the links for PDF, HTML, and epub aren't there. I've made sure that the options for auto-generating PDF and epub are selected in the project settings (https://readthedocs.org/dashboard/writing-fundamentals-guide/edit/).

I've posted a question on StackOverflow here: https://stackoverflow.com/questions/55273652/how-do-you-configure-the-nav-pane-to-show-the-pdf-and-epub-options